In recent years the peroxisome proliferator-activated receptor gamma (PPAR gama) has been shown to play a role in cancer. Several groups have shown that PPAR gama plays an anticancer role in several tissues including breast, prostate and relevent to this proposal, colon. However two groups have shown a procancer role for PPAR gama in the colon. Therefore understanding the role of PPAR gama in preventing or promoting colon cancer is important especially considering the use of ligands for PPAR gama in the treatment of type II diabetes. In addition, PPAR gama is expressed at high levels in the colon, implying a role for PPAR gama colonic growth, function, and development. Therefore the goal of this research proposal is to determine the role of PPAR gamain colon carcingenesis and colon function. The specific aims involve: 1) Critically examining the role of PPAR gama in colon carcinogenesis and 2) Examining the role of PPAR gama as a regulator of colonic epithelial cell growth, differentiation and development in vivo using PPAR gama colon specific knock-out mice.